Process of washing coal and separating refuse therefrom.



N. SHANNON.

PROCESS OF WASHING COAL AND SEPARATING REFUSE THEREFROM.

APPLICATION FILED MAY 22. I908.

Patented July 11, 1916.

ED PATENT OFFGE.

NICHOLAS SHANNON, OF PANAMA, ILLINOIS, ASSIGNOR- TO LINK BELT COMPANY,OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PROCESS OF WASHING COAL AND SEPARATING REFUSE THEREFROM.

and Separatmg Refuse There'from, of which the following is aspecification containing a full, clear, and exact description, referencebeing had to the accompanylng drawlngs,

forming a part hereof.

My invention relates to a process of washing coal and separating refusetherefrom, and the object of my invention is to contribute to the art aprocess wherein coal is submerged and by a jigging action subjected tothe action of a senes of jets of water which are automaticallycontrolled by a selfmaintained bed of'refuse from the coal, as will behereinafter pointed out.

I accomplish the cleaning and separating operations by subjecting acontinuously moving body of coal and refuse to the action of a series ofjets of water. of varying pressure, which action takes place on the downstroke of the jig, or like member, through which the body of coal andrefuse moves, and said body of coal and refuse being subjected to awashing and settling action of the water through the body of coal andrefuse.

In order that my process may be more readily'understood, I have shown inthe accompanying drawing a simple structure, particularly adapted forcarrying out my process, although it will be understood that saidprocess may be accomplished in a variety of ways.

The figure shown in the drawing is a vertical section taken through thecenter of a tank and jig; and, referring by numerals to this drawing, 1designates the tank, Which is divided by vertically disposed partitions2 and 3 into three compartments, A, B and C, the compartment being thecleaned coal compartment, jig compartment, and C the-refuse compartment.

Arranged for vertical reciprocation 1n the compartment B is a verticalldlsppsed ig 4, preferably provided w1 t antlfrictlon rollers 4, whichbear against the part1- tions 2 and 3 to minimize the necessary powerfor the vertical movement of the ig; and rigidly fixed in Specificationof Letters Patent.

the compartment B the after passing beneath the the upper portion ofPatented July '11, 1916.

Application filed May 22, 1908. Serial No. 434,428.

this jig 4 is a perforated plate 5, at or near one end of which isformed an opening 6.

Arranged 0n the plate 5, immediately adacent the opening 6, is avertically disposed wall 7 in the lower portion of which is formed anopening 8, which is adapted to be closed by. a vertically moving gate 9,which is connected to an adjustable hand lever 10 arranged on the upperportion of the jig. I

Extending laterally from the upper portion of the jig 4 and from theupper end of the wall 7 immediately over the partition 2, 1s a cleanedcoal spout 11, provided with side walls, and which spout is slightlyinchned from its outer end toward the wall 7.

Fixed to the upper portion of the jig,

directly opposite this spout 11 and immediately over the inclined upperend of the perforated plate 5, is a hopper 12, through which the-coal tobe cleaned is delivered.

The body of the jig beneath the perforated plate 5 is for the solepurpose of providing means for conserving and directing water pressurescreated by movements of the jig to act on the coal and its refuse.

In .carrying out my process with the structure shown, the jig 4 isvertically reciprocated in any suitable manner and the coal to be washedis continuously delivered into the hopper 12; and said coal passes fromthence downward onto the upper end of the inclined perforated plate.

- It is to be'distinctly understood that coal and its refuse from thetime of their delivery to the jig, during the jigging actions and duringtheir discharge from the jig, are wholly submerged.

The jig is vertically reciprocated and in its downward movement theoperation of the jig beneath. the perforated plate provides a rise inpressure of the water therein contained, thus impellin it through theperforations and causing it to issue into the massof coal and refuse injets of 'sufficient force to elevate the coal and refuse above theplate. Owing to the difference in specific gravities of the coal and itsrefuse a separating and stratifying actlon takes place.

The gate 9- is open to such a degree as desired by means of theadjustable handle 10 and the continuously moving body of refuse, gate 9,will dis charge through the opening 8, and from loo thence downwardthrough the opening 6, and will finally pass into the lower portion ofthe compartment C, from whence it may be removed.

The openings or perforations in the plate are of such size as to preventa material discharge of refuse therethrough so that a bed of the refusewill be continuously maintained upon the plate.

By the provision of a controllably sized outlet for the discharge ofrefuse at a point where it is subjected to the varying water pressures,created by the movement of the jig body, beneath a plate and at a pointremote from the supply, I am enabled to con-' trol the layer or bed ofrefuse on the plate as to character, quantity and disposition.

The removal of the refuse from the machine takes place through acompartment of the tank in communication with the jigging or processcompartment only at its lowermost end, sothat the removal may beeffected during the operation of the process with a minimum ofcontamination and disturbance of the water in the process compartment. 1In addition to the advantage just set forth in the provision of acompartment partially separated from the process compartment I find thesaid refuse compartment acts as a water column communicating with thewater-confining chamber comprising the lower part of the jig.

By virtue of the jigging element being separated from the wall of thejigging compartment there exists a continuous and circuitous passage waythrough the bed of material to be acted upon, and including the spacesurrounding the jigging element, in order that a water circulation maybe maintained therein, whenever the jig is in operation.

During the reciprocating motions of the jig the body of refuse carriedthereby has a sort of valve-like action; it being, during the downwardexcursion of the jig, lifted or held somewhat in suspension by the waterpressure generated in the compressed chamber and acting thereon,permitting a relatively free flow of water through the plate 5 and thesaid body of refuse. During the reverse excursion of the jig the body ofrefuse descends, resting heavily upon the plate 5 and obstructing, theflow of water, through the jet openings in the said plateJ The generalcourse or direction of the flow of water is therefore in a directionupward through the jig, whence it passes outward, some flowin throughthe delivery spout with the coa and the balance, over the top of thejig, and thence downward through the space between the jigging elementand the wall of the compartment in which it operates, and from thenceback into the compression chamber of the jig. It will be noticed that inthis circulation system there is a point where the coal and water aredischarged througha spout.

The coal, on account of the size and weight of the particles thereof,falls abruptly into a relatively stagnant portion of the body of water,while the lighter floating particles of refuse which pass over the topedge of the jig are carried along with the more active circulatingstream. Furthermore, it will be noticed that the passage way between thejigging element and the wall of the jigging compartment is of lesserarea than the space immediately beneath the jig. In consequence of thisrelationship of areas the velocity of this circulating stream is greaterjust prior to the influx of water into the compression chamber than itis before making its turn into the compression chamber. The effect inthis change in velocities is that the particles of refuse are carried tothe bottom of the jigging compartment B, from whence they go into therefuse compartment C and are thereby separated from the circulatingstream which, freed from said refuse, continues its cycle of washingoperation.

It is to be observed that in the present embodiment of my inventionthere is a chamber for securing high and low pressures alternatelyJ Incommunication with this chamber there is a'multiplicity of jetsdecreasing in activity with the trend of travel of material in thejigging element above the said chamber. It is to be observed furtherthat there is a port, namely, the refuse discharge opening,communicating with the same chamber as the said jets, affording streamlines 'at substantially right angles to the flow of the jets, both jetsand port stream Varying their flow proportionately with the alternationsof pressure in the chamber so as tov produce whirls in the wash water byeddy currents and, alternately with these whirls, a motion toward thedischarge end, these two different alternate actions being brought aboutby the valve-like action of the refuse.

Water flowing through the jet openings moves substantially at rightangles to the trend of material, while the water flowing through theport or discharge opening moves substantially parallel with the trend ofthe material. The effect of these two streams of fluid impinging uponeach other at any considerable angle is to produce a whirl or eddycurrent. The purpose of the eddy current, thus established, is toproduce a scouring action upon the material within the jig, to assist infreeing the jet openings in the plate 5 from refuse, and to loosen thebed or stratum of refuse, especially the portion thereof adjacent to thedischarge opening. It will be understood that, since the dischargeopening for the refuse leads directly into the compartment confining thebody of water in which the jig reciprocates, there is no tendency forthe water, on the downward excursion of the jig, to flow across orshort-circuit through the body of refuse, from the jet holes in theplate 5 170 the refuse discharge opening 8, as would be the case shouldthe said opening deliver outside the said confined body of water: forthe inward moving stream of water flowing into the jig through thedischarge opening 8 momentarily checks the discharge of the refuse,lifting it and stirring it up, as has been described, while, on thereturn or upward reciprocation of the jig there is a discharge of therefuse through the said opening.

The water column, which has already been described, is in the refusecompartment and communicates with the jig or process compartment by athroat at the bottom of said compartments, operates to dampen or controlthe alternate pressures to a certain extent in the jet ap aratus or jig.The said throat is so proportioned as to cause the desired activity ofthe jet flow, but it should be never less than a capacity suflicient forthe free exit of refuse.

By subjecting coal and its refuse to jets of water under relatively highpressure at the place in the apparatus where the coal is deliveredthereto,there is obtained not only a powerful washing action but a widedegree of separation between the coal and the refuse washed therefrom.

By gradually diminishing the force of the jets from the receiving end ofthe apparatus to the deliverv end and obtaining a relatively slight etaction at the delivery end, the coal is continuously subjected to awashing action without danger of-discharging refuse with the ,coal atthe delivery end.

This graduated jet pressure is brought about by a self-maintained anduniform bed of refuse material of gradually increasing thickness fromthe receiving to the delivery end of the jig.

In the case of removing fine dust or dirt from coal where the percentageof refuse is small, the discharge gate is closed and the bed of refusealready formed operates in exactly the same manner as above described,the particles of refuse, however, being light are carried out by thecirculating stream of water, in a course already indicated, and over thetop of the jig. The heavier lumps of coal on arriving at the end of thespout drop to the stagnant part of the body of water beneath, while thelighter particles of dirt to be removed from the jig are carried bv themore active stream of water along the general line of circulation. 1

As the water of the stream descends between the side of the jig and thewall of the jigging compartment it makes an abrupt turn at the bottom ofthis passage way. As has already been explained a difference in velocityoccurring here ermits the water to return into the pressure chamber ofthe jig, which is in the course of flow of the circulating water, whilethe particles of refuse that have been separated continue their verticalcourse downward through the throat into the refuse compartment.

It will be seen that the material being treated is moved laterally orhorizontally in a comparatively thin layer, and while moving, as a mass,is subjected to up and down movements beneath the surface of a confinedbody of still water, as distinguished from a flowing stream of water.The effect of this action upon the material is to separate it intostrata, as has been described, the lighter, and, when coal is beingtreated, the valuable, material, constituting the upper stratum, and therefuse material, the lower stratum. These two bodies of material aredelivered out of the machine at different levels, the lighter materialbeing discharged outside of the jig and the compartment in which itoperates, while the heavier refuse material is discharged into the bodyof water confined in said compartment, whereby inequality of action andirregularity of stream movement in the water which is being utilized tostratify the material and loosen the bed of material, is obviated.

The process and apparatus described insures the maintenance f a uniformbed of refuse material during the operation of the apparatus, thedischarge of the refuse being substantially uniform or continuous, andnot tending to disturb the uniform characteristics of the refuse bed, asis the case in the operation of those forms of apparatus where areemployed discharge gates or valves that are intermittently opened to aconsiderable extent or for a. considerable time, permitting thedischarge of the accumulated refuse, after which they are closed,

allowing refuse to accumulate.

By causing the jig to operate in a confined body of water, anddischarging the refuse into this body, short-circuiting of the streamsof water fromthe jet openings in the supporting plate to the refusedischarge opening,with the incident rapid washing out of the refusematerial on the down movements of the jig and the consequent breakingdown or disturbance of the uniform and continuous layer of refusematerial,is prevented, ashas already been pointed out. By subjecting thebed of refuse at its discharge end, and the layer of coal thereon aswell, to the action of counter water currents, some entering through theopenings in the supporting plate 5 and others through the port where therefuse discharges, the material being treated is not only loosened up,as has been pointed out, but the discharge, both of the cleaned coal andthe refuse, is facilitated, the lifting and loosening of the material onthe down stroke of the jig resulting in the discharge of the cleanedcoal and the settling back of the refuse material on the up stroke ofthe jig, resulting in the discharge of the refuse.

Coal washers may be roughly divided into three classes: those whichcontain fixed jigs through which the water is forced; those whichcontain reciprocating jigs which are operated in or against acontinuously moving stream of Water; and those which have jigsreciprocating in still water, that is beneath the surface of a body ofrelatively still water, and in which the coal and refuse matter arecontinuously submerged beneath the surface of such body of water. Thesethree classes will include most if not all coal washers. The washer ofthis application is in the third class. The material to be separated orwashed is moved laterally or horizontally in a comparatively thin layerthrough and substantially beneath the surface of the body 7 of stillwater. The lateral motion is due to the pressure of the oncoming streamof material. The separation is effected by gravity, for the problemdeals with materials of differing specific gravity which have been mixedtogether. To effect this separation the moving mass of material isloosened by reciprocating it vertically, as it passes along, against aconfined body of water, all of the upwardly moving streams, from whichthe confined body of water is directed upwardly through the moving mass,being substantially uniformly distributed therethrough. As the massmoves under these conditions it is separated into two layers of unequalspecific gravity, the lighter being discharged outside of the jig andthe jig tank, while the heavier is discharged into the confined body ofWater whereby disturbances, inequality of action and irregularity ofstream movement in the water which is being utilized to loosen the bedare obviated.

The compartment B may be called the inertia chamber. It is a downwardlyextended compartment about the lower end of the jig, and it confines amass of water which is adapted to be forced upwardly through the coal,or, to put it another way, is adapted when the jig descends to permitthe coal to separate by gravity as it tends to fall through so much ofthe water of such inertia chamber as enters the jig when the jig sodescends.

During the operation the water in the inertia chamber and in thejig maybe thought of as for the most part substantially at rest. The water inthe inertia chamber does not flow upwardly in any quantity, but onlypasses through the perforations in the bottom of the jig while suchperforated bottom is descending through the water. Thus a large amountof Water is in the jig or above the bottom of the jig and therefore thestrata can distribute'themselves widely, measured in a verticaldirection. In other words, its particles separate or settle or tend tostratify, the lighter on top and the heavier toward the bottom. It isessential for successful operation that substantially all of the waterin the jig be confined or be protected from violent lateraldisplacement. Such lateral displacement would occur if the slate orrefuse chamber did not open into the inertia chamber or if it were openat the top. When the jig descends, the entire volume of water Within thejig and Within the inertia chamber remains practically still except sofar as its operation is disturbed by the upward and lateral rush ofwater through the slate chamber into the jig. When the jig descends, thesupport for the material within the jig is removed and the particles ofthe material within the jig being held in suspension immediately beginto descend with unequal velocity according to their specific gravity andarrange themselves in the desired specified form.

I claim The process of separating mixed materials of different specificgravity which consists in moving the same laterally underneath thesurface of a confined body of still water in a continuous stream bymeans of the pressure of the oncoming current of material,reciprocating-said moving stream of material vertically beneath thesurface of such body of water and against a portion thereof confined inan inertia chamber to permit the Stratification of material, dischargingthe light material from above at the end of the stream into onecompartment containing a portion of such still water, the fine heavymaterial into the inertia compartment below, and the coarse heavymaterial from below at the end of the stream into an upwardly inclosedbody of water and thence into the in- I ertia chamber body of water.

In testimony whereof, I havesigned my name to this specification, inpresence of two subscribing Witnesses.

NICHOLAS SHANNON.

Witnesses:

M. P. SMITH, E. L. WALLACE.

